Frequency indicator



July 14, 1931. R E MALLES 1,813,942

FREQUENCY INDICATOR Filed Nov. 26, 1927 V /NVENTUR Arm/#Nay tors.

Patented July 14, 1931 UNITED STATES PATENT OFFICE RALPH E. HALLES, OF BROOKLYN, NEW YORK, ASSIGNOR TO BELL TELEPHONE LABO- RATORIES, INCORPORATED, 0F NEW YORK, N. Y., A CORPORATION OF .NEW YORK FREQUENCY INDICATOR Application led November 26, 1927. Serial N0. 235,831.

This invention relates to clock driving mechanism and more particularly to clocks driven by synchronous motors. i

The object ot this invention is to provide means tor adjusting the hands of the clock without disturbing the synchronism ot the motor. The invention is particularly well adapted for use in the system ot Patent No. 1,560,056 to J. W. Horton issued November 3, '1925 wherein a timing fork oscillation generator is used a standard frequency source to calibrate other oscillation genera- The output of this generator also drives the synchronous motor of a clock which serves to count and indicate the fie quency ot the generator in order that the constancy of the primary generator tren quency may be compared with another standard.

l'n accordance with this invention, an adjusting mechanism is provided for the clock whereby the hands may be turned in either direction while the drive is in motion without the addition of friction which would disturb the synchronism of the driving motor. More specifically, the connection between the motor and clock drive comprises a worm on the. motor shatt and a worm gear on the clock drive to which 4ear is attached the internal or ring gear ot: a system ot planetary gearing. The ring gear drives two planetary pinions mounted on an arm, the sun pinion, with which the planetary pinions mesh, remaining stationary. This arm is directly connected to the second hand shaft of a standard clock movement. The sun pinion can be revolved to set1 thehands of the clock movement either by a knob fastened to a spur gear on the drive proper, or by a worm and gear, the tormer providing for coarse, and the latter tor fine, adjustments.

Other features of the invention and advantages will appear from the following description and by the claims appended thereto, reference being had to the accompanying drawings, in which:

Fig. l is an assembly view ot the device showing the driving motor and its operating circuit schematically: and

Fig. 2 is a side view of the device showing a. portion of the indicators operating mechanism 1n section.

The device of this invention consists of supporting plates `1(l'and 1l which may be held in spaced relation by a number of ordi nary spacing members not shown.

ln plate l0 there is mounted a bushing l2 which extends laterally iheretrmn andisecured by means ot' nut screw i3. In bushing l2 there is rotatably mounted a bushing 1.4 in which the shai't l5 is rotatably mounted and held against lateral movement therein b i an end thrust bearingr in the form ot adjustable` screw 1 6 which is supported by bracket 1T. this bracket being in turn fastened `rto trame plate l() by screws 1S. On the outer extending end portion ot shaft l5 there is mounted a worm gear 19 keyed thereon by pin 2o, This wheel meshes with a worm screw 2] which is journaled at each end portion in brackets 22 and 23 in turn secured on trame plate l0. Worm screw 21, is operatively con-- neeted to a synchronous motor 24 by mitei gears 25 and 26. This motor of ordinary construction and operates on current impulses of cycles per second generated bv tuning fork 88 of an oscillator circuit. not shown. The electrica-l connections between the tuning fork and motor are through an obvious circuit, i

Worm gear 19 carries an internal or ring,r gear 27 secured thereon by a number of laterally extending posts 28. Gear 2T meshes with two satellite pinions 29 and 30 mounted on their respective spindles 36 an 3T earvried by a yoke 31. Pinions 29 and 8O in turn mesh wit i" a normally stationary rack or pinion 32. Yoke 3l is secured on the outer end portion of bushing 14 which is keyed to shaft 33 by avpin 34. (ln the other end portion of--sha-ft 33 there is mounted the ser4 ond hand 35 of the clock.

As shown in Fig. 2 the movement. oi sha t1. 33 to which the hand 35 is connecten is made use of for driving the minute and hour hands through an ordinary clock reduci' gear mechanism. The movement oi sha {"t is imparted to the minute hand through pinion 46 secured en shaft 33, intermcdiar)v gears 47 and 48, gear 49 having a huh por` ed. The movement of sleeve 50 is impartedv to thehour-hand 56 by pinion 52 keyed on fhub portion 5,0. This pinion meshes with intermediary gear 53 carrying pinion-54, in turn engaging gear 55 on the* lub portion of which `the hour hand 56 is mounted. Through the movelnent of the hands 35,51 and 56 the frequency of the generator may thus be conveniently checked. The hands may he adjusted on they time marks by means of fine and coarse setting mechanisms which will be hereinafter described. The fine adjustment mechanism comprises sun Apinion 32 secured on a bushing 57 which in'turn is loosely mounted onbushing 12, On bushing 57 there islooscly mounted a worm gear 58 which meshes .with worm screwr59. This worm screw is keyed on `shaft y6() Awhich in turn is operably connected 4to rshaft 61 through miter gears 62 and 63. On bushing 57 there is mounted acollar 64 which may be moved in adj ustedposition on the threaded portion of bushin 57 and set thereon by screw 65. This colTar cooperates with a spring ring 66 and Worm gear 58-to form a friction clutch device forrotating sun pinion 32 by the manualoperation of knob 67 on shaft 61 and forvpermitting the movement of sleeve 57 and sun pinion 32 carried thereby under control of a coarse adjustment mechanism which comprises knob 7l mounted on shaft 70, and spur gear 69 engaging gear 68 on sleeve 57.

In the operation of the device uthe movement of motor 24 under control of tuning fork 38 is eective to operate Worm gear 19 and ring gear 27 carried thereby through miter gears 25 and 26 and Worm screw 2l. Ring gear 27 imparts-.its movement to satellite pinions 29 and 30 which mesh with the sun pinion 32 and thereby operate yoke 31 and the second hand 35 lcarried thereby. Now assume that the speed of the tuning fork is fast or slow with respect to signals from the master clock and that it is desired to retard or advance the hand 35. This is accomplished by the operation of knob 71 actuating the coarse adjustment mechanism from the rear of the panel, or knob 67 actuating the fine adjustment from the front of the panel. The movement of knob 67 is effective to turn sleeve 57 and rack or sun pinion 32 carried thereb through the friction clutch which inclu es as above lstated spring Washer 66 and collar 64. .The movement of this pinion is effective to impart a relative movement to satellitepinions `29 and and therefore to yoke 31 with respect to the movement imparted thereto by internal gear 27 for changing the position of hand 35.

The setting of hand vmay also be effected through the movement of knob 71 of the coarse adjustment setting mechanism in a manner similar to that described in connection with the fine adjustment above referred to. It is obvious that the movement vof shaft 33 and hand 35 carried thereby is effective to move the pointers 56 and 51 through the gear reduction trains above described an amount proportional to'that of hand 35 in a manner similar to that of an ordinary clock mechanism.

In each setting operation of the hands the movement of sun pinion 32 as above described does not materially affect or change the torque carried by the motor which per? mits. the motor to turn at any instantin accurate synchronism With-the tuning fork.

What is claimed is: 1. vA clock driving mechanism comprising a synchronous motor, a clock reduction gearing and clock hands driven thereby, a

gear reduction train including a yoke operated by said motor to drive the/hands of the clock through said gearing, and manually operable means mounted on the clock for moving said yoke 1n either direction without disturbing the synchronism of the motor.

y2. vA clock driving mechanism comprising a synchronous motor, a clock reduction gear- .ing and second, minute and hour hands driven thereby, a gear reduction train for trans- -mitting the movement of the motor to the clock reductlon gearing including a ring gear driven by the motor, a normally stationary sun pimon, a yoke, planetary pinions carried thereby and meshing with said ring gear -and sun pinion, said yoke being connected to said second hand, a knob on the clock, and vgearing connecting said knob and sun' pinion whereby the sun pinion may be rotated in either of two directions for actuating the clock hands.

3. In an indicator mechanism, a synchronous motor, a driven shaft, a gear mechanism operatively connecting the motor shaft to said driven shaft, a hand carried by the -driven shaft, said mechanism including an shaft with respect to the motor shaft in either of two directions.

In Witness whereof, I hereunto subscribe my name this 16th day of November A. D.

RALPH E. MALLES. 

